1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 Revision 1.14 1999/10/08 06:27:23 fca
19 Corrected bug in the HV degrader geometry, thanks to G.Tabary
21 Revision 1.13 1999/10/04 13:39:54 fca
22 Correct array index problem
24 Revision 1.12 1999/09/29 09:24:34 fca
25 Introduction of the Copyright and cvs Log
29 ///////////////////////////////////////////////////////////////////////////////
31 // Time Projection Chamber version 1 -- detailed TPC and fast simulation //
35 <img src="picts/AliTPCv1Class.gif">
40 ///////////////////////////////////////////////////////////////////////////////
43 #include <TGeometry.h>
55 #include "AliTPCParam.h"
60 //_____________________________________________________________________________
61 AliTPCv1::AliTPCv1(const char *name, const char *title)
62 :AliTPC(name, title) {
64 // Standard constructor for Time Projection Chamber
69 //_____________________________________________________________________________
70 void AliTPCv1::CreateGeometry()
73 // Creates geometry for Time Projection Chamber version 1
74 // Detailed geometry -- Fast simulation
79 <img src="picts/AliTPCv1.gif">
84 <img src="picts/AliTPCv1Tree.gif">
88 AliTPCParam * fTPCParam = &(fDigParam->GetParam());
90 Int_t *idtmed = fIdtmed->GetArray();
98 // ----------------------------------------------------
99 // FIELD CAGE WITH ENDCAPS - G10
100 // THIS IS ALSO A TPC MOTHER VOLUME
101 // ----------------------------------------------------
107 gMC->Gsvolu("TPC ", "TUBE", idtmed[8], dm, 3);
109 //-----------------------------------------------------
110 // Endcap cover c-fibre 0.86% X0
111 //-----------------------------------------------------
117 gMC->Gsvolu("TPEC","TUBE",idtmed[10],dm,3);
119 //-----------------------------------------------------
120 // Drift gas , leave 2 cm at the outer radius
122 //-----------------------------------------------------
128 gMC->Gsvolu("TGAS", "TUBE", idtmed[3], dm, 3);
131 //------------------------------------------------------
132 // membrane holder - carbon fiber
133 //------------------------------------------------------
136 gMC->Gsvolu("TPMH","TUBE",idtmed[6],dm,0);
142 gMC->Gsposp("TPMH",1,"TGAS",0.,0.,0.,0,"ONLY",dm,3);
148 gMC->Gsposp("TPMH",2,"TGAS",0.,0.,0.,0,"ONLY",dm,3);
150 //----------------------------------------------------------
151 // HV membrane - 25 microns of mylar
152 //----------------------------------------------------------
158 gMC->Gsvolu("TPHV","TUBE",idtmed[5],dm,3);
160 gMC->Gspos("TPHV",1,"TGAS",0.,0.,0.,0,"ONLY");
162 gMC->Gspos("TGAS",1,"TPC ",0.,0.,0.,0,"ONLY");
164 //----------------------------------------------------------
165 // "side" gas volume, the same as the drift gas
166 // the readout chambers are placed there.
167 //----------------------------------------------------------
171 dm[2] = 0.5*(275. - 250.);
173 gMC->Gsvolu("TPSG", "TUBE", idtmed[2], dm, 3);
175 Float_t z_side = dm[2]; // 1/2 of the side gas thickness
177 //-----------------------------------------------------------
178 // Readout chambers , 25% of X0, I use Al as the material
179 //-----------------------------------------------------------
181 Float_t InnerOpenAngle = fTPCParam->GetInnerAngle();
182 Float_t OuterOpenAngle = fTPCParam->GetOuterAngle();
184 Float_t InnerAngleShift = fTPCParam->GetInnerAngleShift();
185 Float_t OuterAngleShift = fTPCParam->GetOuterAngleShift();
188 Int_t nInnerSector = fTPCParam->GetNInnerSector()/2;
189 Int_t nOuterSector = fTPCParam->GetNOuterSector()/2;
192 Float_t InSecLowEdge = fTPCParam->GetInSecLowEdge();
193 Float_t InSecUpEdge = fTPCParam->GetInSecUpEdge();
195 Float_t OuSecLowEdge = fTPCParam->GetOuSecLowEdge();
196 Float_t OuSecUpEdge = fTPCParam->GetOuSecUpEdge();
198 Float_t SecThick = 2.225; // Al
200 Float_t edge = fTPCParam->GetEdge();
204 dm[0] = InSecLowEdge*TMath::Tan(0.5*InnerOpenAngle)-edge;
205 dm[1] = InSecUpEdge*TMath::Tan(0.5*InnerOpenAngle)-edge;
206 dm[2] = 0.5*SecThick;
207 dm[3] = 0.5*(InSecUpEdge-InSecLowEdge);
209 Float_t xCenterS = InSecLowEdge+dm[3];
211 gMC->Gsvolu("TRCS", "TRD1", idtmed[0], dm, 4);
215 dm[0] = OuSecLowEdge*TMath::Tan(0.5*OuterOpenAngle)-edge;
216 dm[1] = OuSecUpEdge*TMath::Tan(0.5*OuterOpenAngle)-edge;
217 dm[2] = 0.5*SecThick;
218 dm[3] = 0.5*(OuSecUpEdge-OuSecLowEdge);
220 Float_t xCenterL = OuSecLowEdge+dm[3];
222 gMC->Gsvolu("TRCL", "TRD1", idtmed[0], dm, 4);
224 Float_t z1 = -z_side + SecThick*0.5;
226 //------------------------------------------------------------------
227 // S sectors - "gas sectors" (TRD1)
228 //------------------------------------------------------------------
230 dm[0] = InSecLowEdge*TMath::Tan(0.5*InnerOpenAngle)-0.01;
231 dm[1] = InSecUpEdge*TMath::Tan(0.5*InnerOpenAngle)-0.01;
232 dm[2] = 0.5*(250. - 0.001);
233 dm[3] = 0.5*(InSecUpEdge-InSecLowEdge);
235 gMC->Gsvolu("TSGA", "TRD1", idtmed[3], dm, 4); // nonsensitive
237 //------------------------------------------------------------------
238 // sensitive strips - "pad rows"
239 //------------------------------------------------------------------
244 Float_t StripThick = 0.01; // 100 microns
245 Float_t dead = fTPCParam->GetDeadZone();
247 gMC->Gsvolu("TSST", "TRD1", idtmed[4], dm, 0);
249 dm[2] = 0.5*(250. - 0.002);
250 dm[3] = 0.5 * StripThick;
255 for (ns = 0; ns < fTPCParam->GetNRowLow(); ns++) {
257 r1 = fTPCParam->GetPadRowRadiiLow(ns);
258 r2 = r1 + StripThick;
259 dm[0] = r1 * TMath::Tan(0.5*InnerOpenAngle) - dead;
260 dm[1] = r2 * TMath::Tan(0.5*InnerOpenAngle) - dead;
262 zz = -InSecLowEdge -0.5*(InSecUpEdge-InSecLowEdge);
266 gMC->Gsposp("TSST", ns+1, "TSGA", 0., 0., zz, 0, "ONLY", dm, 4);
271 //-----------------------------------------------------------------
272 // L sectors - "gas sectors" (PGON to avoid overlaps)
273 //-----------------------------------------------------------------
275 dm[0] = 360.*kDegrad - 0.5*OuterOpenAngle;
277 dm[0] = (Float_t)TMath::Nint(dm[0]);
279 dm[1] = OuterOpenAngle*kRaddeg;
280 dm[1] = (Float_t)TMath::Nint(dm[1]);
286 dm[5] = OuSecLowEdge;
287 dm[6] = 252.*TMath::Cos(0.5*OuterOpenAngle)-0.002;
294 dm[11] = OuSecLowEdge;
295 dm[12] = OuSecUpEdge;
301 gMC->Gsvolu("TLGA","PGON",idtmed[3],dm,16);
303 //------------------------------------------------------------------
304 // sensitive strips - "pad rows"
305 //------------------------------------------------------------------
307 Float_t rmax = dm[6];
311 gMC->Gsvolu("TLST", "PGON", idtmed[4], dm, 0);
313 dm[0] = 360.*kDegrad - 0.5*OuterOpenAngle;
315 dm[0] = (Float_t)TMath::Nint(dm[0]);
317 dm[1] = OuterOpenAngle*kRaddeg;
318 dm[1] = (Float_t)TMath::Nint(dm[1]);
325 Float_t xx = dead/TMath::Tan(0.5*OuterOpenAngle);
327 for(ns=0;ns<fTPCParam->GetNRowUp();ns++){
329 r1 = fTPCParam->GetPadRowRadiiUp(ns)-xx;
330 r2 = r1 + StripThick;
345 gMC->Gsposp("TLST",ns+1,"TLGA",xx,0.,0.,0,"ONLY",dm,10);
349 //------------------------------------------------------------------
350 // Positioning of the S-sector readout chambers
351 //------------------------------------------------------------------
353 Float_t zs = 0.5*(250.+0.002);
355 Float_t theta1,theta2,theta3;
356 Float_t phi1,phi2,phi3;
360 for(ns=0;ns<nInnerSector;ns++){
362 phi1 = ns * InnerOpenAngle + 270.*kDegrad + InnerAngleShift;
363 phi1 *= kRaddeg; // in degrees
365 phi1 = (Float_t)TMath::Nint(phi1);
367 if (phi1 > 360.) phi1 -= 360.;
373 phi3 = ns * InnerOpenAngle + InnerAngleShift;
374 phi3 *= kRaddeg; // in degrees
376 phi3 = (Float_t)TMath::Nint(phi3);
378 if(phi3 > 360.) phi3 -= 360.;
382 alpha = phi3*kDegrad;
384 x = xCenterS * TMath::Cos(alpha);
385 y = xCenterS * TMath::Sin(alpha);
387 AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
389 gMC->Gspos("TRCS", ns+1, "TPSG", x, y, z1, idrotm[nRotMat], "ONLY");
391 gMC->Gspos("TSGA",ns+1,"TGAS",x,y,zs,idrotm[nRotMat], "ONLY");
392 gMC->Gspos("TSGA",ns+1+nInnerSector,"TGAS",x,y,-zs,idrotm[nRotMat], "ONLY");
398 //-------------------------------------------------------------------
399 // Positioning of the L-sectors readout chambers
400 //-------------------------------------------------------------------
402 for(ns=0;ns<nOuterSector;ns++){
403 phi1 = ns * OuterOpenAngle + 270.*kDegrad + OuterAngleShift;
404 phi1 *= kRaddeg; // in degrees
406 phi1 = (Float_t)TMath::Nint(phi1);
409 if (phi1 > 360.) phi1 -= 360.;
414 phi3 = ns * OuterOpenAngle+OuterAngleShift;
415 phi3 *= kRaddeg; // in degrees
417 phi3 = (Float_t)TMath::Nint(phi3);
420 if(phi3 > 360.) phi3 -= 360.;
424 alpha = phi3*kDegrad;
426 x = xCenterL * TMath::Cos(alpha);
427 y = xCenterL * TMath::Sin(alpha);
429 AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
432 gMC->Gspos("TRCL", ns+1, "TPSG", x, y, z1, idrotm[nRotMat], "ONLY");
438 //-------------------------------------------------------------------
439 // Positioning of the L-sectors (gas sectors)
440 //-------------------------------------------------------------------
442 for(ns=0;ns<nOuterSector;ns++){
444 phi1 = ns*OuterOpenAngle + OuterAngleShift;
447 phi1 = (Float_t)TMath::Nint(phi1);
448 if(phi1>360.) phi1 -= 360.;
453 if(phi2>360.) phi2 -= 360.;
460 alpha = phi1*kDegrad;
463 AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
466 gMC->Gspos("TLGA",ns+1,"TGAS" ,0.,0.,0.,idrotm[nRotMat],"ONLY");
475 AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
477 gMC->Gspos("TLGA",ns+1+nOuterSector,"TGAS" ,0.,0.,0.,idrotm[nRotMat],"ONLY");
482 Float_t z0 = z_side - 0.95;
484 gMC->Gspos("TPEC",1,"TPSG",0.,0.,z0,0,"ONLY");
486 // ==========================================================
488 // ==========================================================
491 // auxilary structures
495 gMC->Gsvolu("TPWI","TUBE",idtmed[24],dm,0); // "air"
497 // ----------------------------------------------------------
498 // Large wheel -> positioned in the TPC
499 // ----------------------------------------------------------
502 z0 = 263.5; // TPC length - 1/2 spoke wheel width
508 gMC->Gsvolu("TPWL", "TUBE", idtmed[0], dm, 3);
514 gMC->Gsposp("TPWI",1,"TPWL",0.,0.,0.,0,"ONLY",dm,3);
516 gMC->Gspos("TPWL", 1, "TPC ", 0, 0, z0, 0, "ONLY");
517 gMC->Gspos("TPWL", 2, "TPC ", 0, 0, -z0, 0, "ONLY");
520 // Outer vessel + CO2 HV degrader
527 gMC->Gsvolu("TPCO","TUBE",idtmed[12],dm,3);
532 gMC->Gsvolu("TPOV","TUBE",idtmed[10],dm,3);
534 gMC->Gspos("TPOV",1,"TPCO",0.,0.,0.,0,"ONLY");
543 gMC->Gsvolu("TPG1","TUBE",idtmed[8],dm,3);
544 gMC->Gspos("TPG1",1,"TPCO",0.,0.,251.,0,"ONLY");
545 gMC->Gspos("TPG1",2,"TPCO",0.,0.,-251.,0,"ONLY");
547 gMC->Gspos("TPCO",1,"TPC ",0.,0.,0.,0,"ONLY");
550 //----------------------------------------------------------
551 // Small wheel -> positioned in "side gas
552 //----------------------------------------------------------
558 gMC->Gsvolu("TPWS", "TUBE", idtmed[0], dm, 3);
564 gMC->Gsvolu("TPW1", "TUBE", idtmed[2], dm, 3);
566 gMC->Gspos("TPW1", 1, "TPWS", 0., 0., 0., 0, "ONLY");
568 z0 = 1.; // spoke wheel is shifted w.r.t. center of the "side gas"
570 gMC->Gspos("TPWS", 1, "TPSG", 0, 0, z0, 0, "ONLY");
579 gMC->Gsvolu("TPS1","TUBE",idtmed[0],dm,3);
583 gMC->Gsvolu("TPS2","TUBE",idtmed[24],dm,3);
585 gMC->Gspos("TPS2",1,"TPS1",0.,0.,0.,0,"ONLY");
589 gMC->Gspos("TPS1",1,"TPC ",0.,0.,z0,0,"ONLY");
590 gMC->Gspos("TPS1",2,"TPC ",0.,0.,-z0,0,"ONLY");
598 gMC->Gsvolu("TPG2","TUBE",idtmed[8],dm,3);
602 gMC->Gspos("TPG2",1,"TPC ",0.,0.,z0,0,"ONLY");
603 gMC->Gspos("TPG2",2,"TPC ",0.,0.,-z0,0,"ONLY");
606 //---------------------------------------------------------
607 // central wheel 6 (radial direction) x 4 (along z) cm2
608 //---------------------------------------------------------
614 gMC->Gsvolu("TPWC","TUBE",idtmed[0],dm,3);
620 gMC->Gsposp("TPWI",2,"TPWC",0.,0.,0.,0,"ONLY",dm,3);
622 z0 = z_side - 1.9 - 2.;
624 gMC->Gspos("TPWC",1,"TPSG",0.,0.,z0,0,"ONLY");
628 gMC->Gsvolu("TPSE","BOX ",idtmed[24],dm,0); // "empty" part of the spoke
631 //---------------------------------------------------------
632 // inner spokes (nSectorInner)
633 //---------------------------------------------------------
635 dm[0] = 0.5*(139.9-82.1);
639 Float_t x1 = dm[0]+82.;
641 gMC->Gsvolu("TPSI","BOX",idtmed[0],dm,3);
646 gMC->Gsposp("TPSE",1,"TPSI",0.,0.,0.,0,"ONLY",dm,3);
648 for(ns=0;ns<nInnerSector;ns++){
650 phi1 = 0.5*InnerOpenAngle + ns*InnerOpenAngle + InnerAngleShift;
654 phi1 = (Float_t)TMath::Nint(phi1);
655 if(phi1>360.) phi1 -= 360.;
658 if(phi2>360.) phi2 -= 360.;
663 alpha = phi1 * kDegrad;
664 x = x1 * TMath::Cos(alpha);
665 y = x1 * TMath::Sin(alpha);
667 AliMatrix(idrotm[nRotMat],theta1,phi1,theta2,phi2,theta3,phi3);
669 gMC->Gspos("TPSI",ns+1,"TPSG",x,y,z0,idrotm[nRotMat],"ONLY");
675 //-------------------------------------------------------------
676 // outer spokes (nSectorOuter)
677 //-------------------------------------------------------------
679 dm[0] = 0.5*(257.9-146.1);
685 gMC->Gsvolu("TPSO","BOX ",idtmed[0],dm,3);
690 gMC->Gsposp("TPSE",2,"TPSO",0.,0.,0.,0,"ONLY",dm,3);
692 for(ns=0;ns<nOuterSector;ns++){
694 phi1 = 0.5*OuterOpenAngle + ns*OuterOpenAngle + OuterAngleShift;
698 phi1 = (Float_t)TMath::Nint(phi1);
699 if(phi1>360.) phi1 -= 360.;
702 if(phi2>360.) phi2 -= 360.;
707 alpha = phi1 * kDegrad;
708 x = x1 * TMath::Cos(alpha);
709 y = x1 * TMath::Sin(alpha);
711 AliMatrix(idrotm[nRotMat],theta1,phi1,theta2,phi2,theta3,phi3);
713 gMC->Gspos("TPSO",ns+1,"TPSG",x,y,z0,idrotm[nRotMat],"ONLY");
721 // --------------------------------------------------------
722 // put the readout chambers into the TPC
723 // --------------------------------------------------------
732 AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
736 gMC->Gspos("TPSG", 1, "TPC ", 0, 0, z0, 0, "ONLY");
737 gMC->Gspos("TPSG", 2, "TPC ", 0, 0, -z0, idrotm[nRotMat], "ONLY");
739 gMC->Gspos("TPC ", 1, "ALIC", 0, 0, 0, 0, "ONLY");
741 //----------------------------------------------------
742 // Inner vessel and HV degrader
743 //----------------------------------------------------
765 gMC->Gsvolu("TPVD", "PCON", idtmed[12], dm, 15); // CO2
782 gMC->Gsvolu("TIVC","PCON",idtmed[11],dm,9); // C-fibre
784 gMC->Gspos("TIVC",1,"TPVD",0.,0.,0.,0,"ONLY");
785 gMC->Gspos("TIVC",2,"TPVD",0.,0.,0.,idrotm[nRotMat],"ONLY");
793 gMC->Gsvolu("TIVB","TUBE",idtmed[9],dm,3);
795 gMC->Gspos("TIVB",1,"TPVD",0.,0.,0.,0,"ONLY");
797 gMC->Gspos("TPVD",1,"ALIC",0.,0.,0.,0,"ONLY");
803 // ---------------------------------------------------
805 // ---------------------------------------------------
806 gMC->Gsord("TGAS", 6);
807 gMC->Gsord("TPSG", 6);
808 gMC->Gsord("TSGA", 3);
809 gMC->Gsord("TLGA", 4);
814 //_____________________________________________________________________________
815 void AliTPCv1::DrawDetector()
818 // Draw a shaded view of the Time Projection Chamber version 1
821 // Set everything unseen
822 gMC->Gsatt("*", "seen", -1);
824 // Set ALIC mother transparent
825 gMC->Gsatt("ALIC","SEEN",0);
827 // Set the volumes visible
828 gMC->Gsatt("TPC","SEEN",0);
829 gMC->Gsatt("TGAS","SEEN",0);
830 gMC->Gsatt("TPSG","SEEN",0);
831 gMC->Gsatt("TPHV","SEEN",1);
832 gMC->Gsatt("TPMH","SEEN",1);
833 gMC->Gsatt("TPEC","SEEN",0);
834 gMC->Gsatt("TRCS","SEEN",1);
835 gMC->Gsatt("TRCL","SEEN",1);
836 gMC->Gsatt("TPWL","SEEN",1);
837 gMC->Gsatt("TPWI","SEEN",1);
838 gMC->Gsatt("TPWS","SEEN",1);
839 gMC->Gsatt("TPW1","SEEN",1);
840 gMC->Gsatt("TPS1","SEEN",1);
841 gMC->Gsatt("TPS2","SEEN",1);
842 gMC->Gsatt("TPG1","SEEN",1);
843 gMC->Gsatt("TPG2","SEEN",1);
844 gMC->Gsatt("TPWC","SEEN",1);
845 gMC->Gsatt("TPSI","SEEN",1);
846 gMC->Gsatt("TPSO","SEEN",1);
847 gMC->Gsatt("TPCO","SEEN",1);
848 gMC->Gsatt("TPOV","SEEN",1);
849 gMC->Gsatt("TPVD","SEEN",1);
851 gMC->Gdopt("hide", "on");
852 gMC->Gdopt("shad", "on");
853 gMC->Gsatt("*", "fill", 7);
854 gMC->SetClipBox(".");
855 gMC->SetClipBox("*", 0, 1000, -1000, 1000, -1000, 1000);
857 gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
858 gMC->Gdhead(1111, "Time Projection Chamber");
859 gMC->Gdman(18, 4, "MAN");
860 gMC->Gdopt("hide","off");
863 //_____________________________________________________________________________
864 void AliTPCv1::CreateMaterials()
867 // Define materials for Time Projection Chamber
869 AliTPC::CreateMaterials();
872 //_____________________________________________________________________________
873 void AliTPCv1::Init()
876 // Initialises TPC detector after it has been created
879 fIdSens1=gMC->VolId("TLST"); // L-sector
880 fIdSens2=gMC->VolId("TSST"); // S-sector
882 printf("TPC version 1 initialized\n");
885 //_____________________________________________________________________________
886 void AliTPCv1::StepManager()
889 // Called at every step in the Time Projection Chamber
895 TClonesArray &lhits = *fHits;
897 AliTPCParam *fTPCParam = &(fDigParam->GetParam());
901 if(gMC->TrackCharge() && gMC->IsTrackEntering()) {
903 // Only entering charged tracks
905 if((id=gMC->CurrentVolID(copy))==fIdSens1) {
909 vol[1]=copy-1; // row
910 id=gMC->CurrentVolOffID(1,copy);
911 vol[0]=copy+fTPCParam->GetNInnerSector()-1; // sector
912 } else if(id==fIdSens2) {
916 vol[1]=copy-1; // row
917 id=gMC->CurrentVolOffID(1,copy); // sector
921 gMC->TrackPosition(p);
922 for(i=0;i<3;++i) hits[i]=p[i];
924 new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);